Influence of subglacial conditions on ice stream dynamics: Seismic and potential field data from Pine Island Glacier, West Antarctica
We interpret seismic reflection and airborne potential field data acquired on Pine Island Glacier, West Antarctica and find variations in the subglacial geology which correlate with variations in ice dynamics. Immediately beneath the glacier is a mixture of soft, deforming sediments and harder, non-...
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ftnerc:oai:nora.nerc.ac.uk:502341 2023-05-15T13:48:07+02:00 Influence of subglacial conditions on ice stream dynamics: Seismic and potential field data from Pine Island Glacier, West Antarctica Smith, Andrew M. Jordan, Tom A. Ferraccioli, Fausto Bingham, Robert G. 2013-04 text http://nora.nerc.ac.uk/id/eprint/502341/ https://nora.nerc.ac.uk/id/eprint/502341/1/jgrb50012.pdf http://onlinelibrary.wiley.com/doi/10.1029/2012JB009582/abstract https://doi.org/10.1029/2012JB009582 en eng https://nora.nerc.ac.uk/id/eprint/502341/1/jgrb50012.pdf Smith, Andrew M. orcid:0000-0001-8577-482X Jordan, Tom A. orcid:0000-0003-2780-1986 Ferraccioli, Fausto orcid:0000-0002-9347-4736 Bingham, Robert G. 2013 Influence of subglacial conditions on ice stream dynamics: Seismic and potential field data from Pine Island Glacier, West Antarctica. Journal of Geophysical Research: Solid Earth, 118 (4). 1471-1482. https://doi.org/10.1029/2012JB009582 <https://doi.org/10.1029/2012JB009582> Glaciology Publication - Article PeerReviewed 2013 ftnerc https://doi.org/10.1029/2012JB009582 2023-02-04T19:37:13Z We interpret seismic reflection and airborne potential field data acquired on Pine Island Glacier, West Antarctica and find variations in the subglacial geology which correlate with variations in ice dynamics. Immediately beneath the glacier is a mixture of soft, deforming sediments and harder, non-deforming sediments. Beneath this, a sedimentary basin lies under part of the main glacier, with another under one of its slower-moving tributaries. A tectonic boundary underlies the main trunk of the glacier separating these sedimentary basins to the north from crystalline rocks to the south, which also include a thick, rift-related magmatic intrusion. The boundary correlates with changes in the basal roughness, ice flow speed, and basal drag. Smoother bed, faster flow, and lower basal drag characterize the thicker sedimentary sequences, to the north, but there is no corresponding lateral change in the acoustic properties of the bed. Changes in the sub-bed (i.e., deeper than the ice-bed interface) lithology appear to account for the contrasting basal drag and ice velocity patterns over the glacier. Subglacial erosion could remove a thin layer of soft sediments to the south of the geological boundary, leading to increased basal drag and reduced ice flow in the future. We conclude that the subglacial geology plays a significant role in controlling the spatial pattern of present-day ice flow and that the consequences of subglacial erosion may be reflected in temporal changes to the ice dynamics in the past and perhaps also in the near future. Article in Journal/Newspaper Antarc* Antarctica Antarctica Journal Pine Island Pine Island Glacier West Antarctica Natural Environment Research Council: NERC Open Research Archive West Antarctica Pine Island Glacier ENVELOPE(-101.000,-101.000,-75.000,-75.000) Journal of Geophysical Research: Solid Earth 118 4 1471 1482 |
institution |
Open Polar |
collection |
Natural Environment Research Council: NERC Open Research Archive |
op_collection_id |
ftnerc |
language |
English |
topic |
Glaciology |
spellingShingle |
Glaciology Smith, Andrew M. Jordan, Tom A. Ferraccioli, Fausto Bingham, Robert G. Influence of subglacial conditions on ice stream dynamics: Seismic and potential field data from Pine Island Glacier, West Antarctica |
topic_facet |
Glaciology |
description |
We interpret seismic reflection and airborne potential field data acquired on Pine Island Glacier, West Antarctica and find variations in the subglacial geology which correlate with variations in ice dynamics. Immediately beneath the glacier is a mixture of soft, deforming sediments and harder, non-deforming sediments. Beneath this, a sedimentary basin lies under part of the main glacier, with another under one of its slower-moving tributaries. A tectonic boundary underlies the main trunk of the glacier separating these sedimentary basins to the north from crystalline rocks to the south, which also include a thick, rift-related magmatic intrusion. The boundary correlates with changes in the basal roughness, ice flow speed, and basal drag. Smoother bed, faster flow, and lower basal drag characterize the thicker sedimentary sequences, to the north, but there is no corresponding lateral change in the acoustic properties of the bed. Changes in the sub-bed (i.e., deeper than the ice-bed interface) lithology appear to account for the contrasting basal drag and ice velocity patterns over the glacier. Subglacial erosion could remove a thin layer of soft sediments to the south of the geological boundary, leading to increased basal drag and reduced ice flow in the future. We conclude that the subglacial geology plays a significant role in controlling the spatial pattern of present-day ice flow and that the consequences of subglacial erosion may be reflected in temporal changes to the ice dynamics in the past and perhaps also in the near future. |
format |
Article in Journal/Newspaper |
author |
Smith, Andrew M. Jordan, Tom A. Ferraccioli, Fausto Bingham, Robert G. |
author_facet |
Smith, Andrew M. Jordan, Tom A. Ferraccioli, Fausto Bingham, Robert G. |
author_sort |
Smith, Andrew M. |
title |
Influence of subglacial conditions on ice stream dynamics: Seismic and potential field data from Pine Island Glacier, West Antarctica |
title_short |
Influence of subglacial conditions on ice stream dynamics: Seismic and potential field data from Pine Island Glacier, West Antarctica |
title_full |
Influence of subglacial conditions on ice stream dynamics: Seismic and potential field data from Pine Island Glacier, West Antarctica |
title_fullStr |
Influence of subglacial conditions on ice stream dynamics: Seismic and potential field data from Pine Island Glacier, West Antarctica |
title_full_unstemmed |
Influence of subglacial conditions on ice stream dynamics: Seismic and potential field data from Pine Island Glacier, West Antarctica |
title_sort |
influence of subglacial conditions on ice stream dynamics: seismic and potential field data from pine island glacier, west antarctica |
publishDate |
2013 |
url |
http://nora.nerc.ac.uk/id/eprint/502341/ https://nora.nerc.ac.uk/id/eprint/502341/1/jgrb50012.pdf http://onlinelibrary.wiley.com/doi/10.1029/2012JB009582/abstract https://doi.org/10.1029/2012JB009582 |
long_lat |
ENVELOPE(-101.000,-101.000,-75.000,-75.000) |
geographic |
West Antarctica Pine Island Glacier |
geographic_facet |
West Antarctica Pine Island Glacier |
genre |
Antarc* Antarctica Antarctica Journal Pine Island Pine Island Glacier West Antarctica |
genre_facet |
Antarc* Antarctica Antarctica Journal Pine Island Pine Island Glacier West Antarctica |
op_relation |
https://nora.nerc.ac.uk/id/eprint/502341/1/jgrb50012.pdf Smith, Andrew M. orcid:0000-0001-8577-482X Jordan, Tom A. orcid:0000-0003-2780-1986 Ferraccioli, Fausto orcid:0000-0002-9347-4736 Bingham, Robert G. 2013 Influence of subglacial conditions on ice stream dynamics: Seismic and potential field data from Pine Island Glacier, West Antarctica. Journal of Geophysical Research: Solid Earth, 118 (4). 1471-1482. https://doi.org/10.1029/2012JB009582 <https://doi.org/10.1029/2012JB009582> |
op_doi |
https://doi.org/10.1029/2012JB009582 |
container_title |
Journal of Geophysical Research: Solid Earth |
container_volume |
118 |
container_issue |
4 |
container_start_page |
1471 |
op_container_end_page |
1482 |
_version_ |
1766248652600246272 |